The one thing the stock IC can benefit from is a good cleaning, off the car, rinsed a couple times w/cheap gasoline until it flows out clear. After so many years, they can suffer from being oil coated inside with a reduction in heat shedding ability.
It's also a good time to straighten fins, confirm the air flow baffles are intact and add a small fan.
As far as the tubes, there is an entire science behind extrude flow honing and certain coatings that help throw heat out and block engine bay heat in, but those aren't cheap, and it can be a hard ROI, where that money could go into a FMIC, etc.